Color converting apparatus and a color converting method

摘要

As image processing apparatus includes a color converter 20 as a color converting device. The color converter 20 has, as main functional components for carrying out color conversion of halftone of a spot color, a spot color information acquiring unit 21 for acquiring spot color information from manuscript data, a spot color Lab acquiring unit 22 for acquiring L*a*b* values in an L*a*b* color space when the dot percentage of the spot color is 100%, a first calculating unit 23 for calculating halftone L*a*b* values, using the L*a*b* values at 100% dot percentage of the spot color acquired by the spot color Lab acquiring unit 22 and a dot percentage of the spot color in a printing target portion of the spot color, and a second calculating unit 24 for converting, using an output ICC profile, the halftone L*a*b* values calculated by the first calculating unit 23 into CMYK values.

主权项

1. A color converting apparatus for converting a device-independent color space into a printing color space dependent on colors of color material loaded in a printing machine, comprising:
an input port for receiving manuscript data for printing in the printing machine, including data calling for a spot color; one or more processors to execute color conversion for printing in which the spot color is reproduced in the printing machine not loaded with the spot color as a color material by using a plurality of other color materials loaded in the printing machine, the one or more processors configured to:
calculate halftone color values of the spot color in the device-independent color space by connecting with a line, in the device-independent color space, maximum color values of a time when a dot percentage of the spot color is at a maximum, and minimum color values of a time when the dot percentage of the spot color is at a minimum; and calculate printing color values in the printing color space from the calculated halftone color values of the spot color in the device-independent color space; and an output port for transmitting the printing color values to the printing machine for printing with the color material loaded in the printing machine.